A printing apparatus, which receives print data including character codes from an external apparatus such as a host computer or the like, reads out font information corresponding to the character codes from an internal font memory, renders the character codes into pattern information, and prints them out, is known.
In recent years, such character codes include those which can designate pictorial symbols used in mobile phones and the like other than the Japanese Industrial Standard (JIS) character codes, and it is demanded to make colorful print of color pictorial symbols and the like using these character codes.
In order to print such color pictorial symbols with good quality, the number of tone levels (tones) per pixel of a pictorial symbol must be increased. As an example that pertains to printing of color character fonts, Japanese Patent Laid-Open Nos. 8-169142, 10-129041 and the like disclose printing color pictorial symbols. However, these references handle fonts of color pictorial symbols as binary bitmaps, resulting in poor appearance of the printed image.
In order to print clear pictorial symbols, font data of such pictorial symbols may be stored as 8-bit (256-level) in each color of RGB or CMY. However, with this arrangement, a large memory size is required to store the font data of pictorial symbol data, resulting in an increase in cost. Furthermore, upon converting such multi-valued data into bitmap image data (binary data), a printing apparatus requires an n-valued conversion process such as error diffusion, multi-valued dithering, and the like, resulting in a low print speed.